Improvement in steam-boilers



UNITED STATES PATENT OFFICE.

JOHN E. NEILL,.OF BROOKLYN, NEW YORK.

IMPROVEMENT IN STEAM-BOILERS.

Specification forming part of Letters Patent No. 45,1 39, dated January 3, 1865.

To all tof/10m it may concern:

Be it known that I, JOHN E. NEILL, of

Brooklyn, in the county of Kings and State ot' New York, have invented a new and useful Improvement in Steam-Boilers for Super-heating Steam; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanyin g drawings, making part ot' this specincation, in which- Figure l is a longitudinal vertical section ot a tubular boiler with my said improvement, and Fig. 2 a cross-section taken at the line A a ot' Fig. l.

The same letters indicate like parts in both figures.

The object of my said invention is to facilitate the superheating of steam in the same boiler in which it is generated, and although my said improvement is applicable to the generality of tubular boilers, whether the water to be generated into steam be made to circulate through or around the tubes, I prefer to apply it to what is known as the Montgomery boiler,77 and sometimes called the Martin boiler,77 and therefore I will describe and represent it as being so applied.

In the accompanying drawin gs, a represents the outer shell of the boiler, and b a series of furnaces, communicating at the rear end by a series ot' dues, c, with the insidel of what are called the tube-boxes 7 d, the said tube-boxes' being iluespaces, through which the products of combustion from the furnaces circulate on their way to the chimney e. The tube-boxes consist of a top and bottom tube-sheet, ff, in which are secured the ends of a series ot" vertical water-tubes, g, and two vertical sheets, /L It, which form the outsides of the said iiue or tube boxes and the insides of the vertical water-spaces t' i, that connect the lower and upper portions of the body ofthe boiler. The heated products of combustion, in passing through the flue-spaces or tube-boxes, act on the outer surface ot' the series of vertical tubes, and thereby heat the water contained in them, and by rarefaction induce the water to rise in them and to descend in the surrounding water-spaces i t'. In this way a rapid circulation of the water is induced through the tubes, the steam evolved rising into the steam-chambery' above.

For the purpose ot superheatin g the steam generated in such a boiler, I take one,two,or a greater number of the said tube-boxes, depending on the capacity ofthe boiler. In the example given in the accompanying drawings I have taken two and' extend the outer side sheets or plates, h h, ot' each tube-box above the water-line ot' the boiler and nearly up to the root'of the boiler, as at k k, and I also eX- tend two outer ones down below the bottom tube-sheet,f, a short distance, as shown atl l; and I sec-ure to the upper tube-sheet, j', other vertical plates7 m m and m' m', the two, m m, at the front edges of the tube-sheets, and the other two, m m', within a short distance ot' the rear end, and unite these by watertight joints with the ends of the side sheets or plates, h It, to form boxes or steam-chambers 'n n, extending some distance above the waterline of the boiler; and I apply two corresponding plates, 0, to the bottom tube-sheets, j" f', and secure them to the beforenamed outside plates, l l, and to these I secure a bottom plate, p. In this way I form two steam-chambers, a a, above the tubes g, and open at top to receive steam from the steamchamber of the boiler and to supply it to the upper ends ofthe said tubes g, and one, q, at the bottom to receive the steam after it has been superheated by passing through the said tubes. The bot tom chamber, q, must be provided with suitable means for carrying oft' the superheated steam to theplace where it is to be used, which may bedone by extending the upper tubesheet, j', and the bottom plate, p, of the bottom steam-chamber, q, to the side ofthe shell ofthe boiler, and adding two end plates to form a steam-passage, r, communicating with the steamchamber q, and provided with a suitable nozzle, s, passing through the shell of the boiler, to which a steam-pipe may be secured. The usual water-space, i, is left between the two tube-boxes communicating at the ends with the water in the boiler. I do not extend the steam-chambers n n andq to the rear end of the tube-boxes, but I prefer, as represented, to leave some of the tubes at the rear end as watertubes, for the reason that these, being nearest to the furnaces, are exposed to very high heat, and are protected against injury from such high heat by the circulation of water through them.

It will be obvious from the foregoing that any portion of the water-tubes of such a boiler can be transformed into superheatingtubes by the application of my said invention; and it will be equally obvious to engineers that my said invention is applicable to other tubular boilers7 Whether the tubes be horizontal7 vertical, or inclined, and whether the tubes of such boilers be arranged as uetubes or Water-tubes. If they-be Water-tubes7 the box applied at one end must be in communication with the steamchamber of the boiler, and the box at the other end must be provided with suitable means for the discharge of the superheatcd steam; and it they be nue-tubes, then that portion of the uetubes of the boiler selected for the purpose must be incased, so that steam from the steamchamber of the boiler shall pass around the said tubes, to be superheated, and then be conducted ot't'to the place where it is to be used.

The proportion of the tubes of a boiler which are to be taken for this purpose will depend upon the extent to which it may be desired to superheat steam and upon what proportion of the steam generated in the boiler may be required to be superheated, and therefore this must be left Wholly to the judgment of the constructor.

I do not wish to be understood as making claim, broadly, in this application to the placing ot` a superheating apparatus Within a tube box or boxes or Within the Hue space or spaces of a steam-boiler, having made that the sub ject of another application of prior date to this, and noW pending. A

What I claim as my invention, and desire to secure by Letters Patent, i`

l. Inca-sing a portion of the tubes of a tubular steam-boiler, substantially as herein de scribed, so that such casing shall extend on one side to the steam-chamber of the boiler, to receive steam generated in the boiler and conduct it to the tubes so incased, to bethereby superheated, and on the other side communicate with the outside of the boiler, to carry off the steam after it has been superheated, substantially as described.

2. Combining with superheating-tubes, or the equivalents thereof', a water tube or tubes, or the equivalent thereof, for the protection of the tubes or iues of a superheater against the intense heat of the products ot' combustion by causing such products to act first on surfaces protected by water7 substantially as herein described.

JOHN E. NEILL. Witnesses A. DE LACY, WM. H. BIsHoP. 

